Operant Behavior
and Operant Contingencies
AILUN – 2008
Lecture 2 – S Glenn
Behavior
• “The action of the organism upon the outside world” (p.6) 1
– Action = movement + effect
• Ongoing behavior is an ever-changing stream of
movements and the effects of those movements on the
world http://www.youtube.com/watch?v=u9E9HpuJQ7U
• Some movements and their effects seem to be organized so
that they have a combined effect
– Ex: Behavior of “cooking a dinner” involves many
movements having local effects and the combined effect
of the entire sequence of movements
– Ex: The behavior of “writing a novel” involves many
sequences of movement having local and combined
effects that all together result in the completed
manuscript
Experimental Model of Behavior
• Purpose is to identify fundamental measurable properties of behavior
and explain their occurrence
– The behavioral analog of atoms in physics, molecules in chemistry, cells in
biology
– Take the world apart to be able to understand how it works
• Need to reduce complexity to a minimum to get to basic building blocks
• Skinner’s model: Pressing a lever or key that closes an electrical circuit
(behavior called “key pressing”)1, 2
– May be measured by counting switch closures over specified interval of
time
– May be measured by timing intervals between switch closures
– May be measured by timing duration of movements that lead to switch
closures
– May be measured by timing interval from occurrence of some event and
the first switch closure after that occurrence
– May be measured by relation of occurrences of switch closures to
occurrences of some antecedent event(s)
Operant Behavior
• Some actions have consequences
– This relation is expressed R->C
– The name for this relation is two-term contingency
– Example
R = Movement (putting the match to the food) + effect (sudden flame)
C = Exclamations of diners
• In experimental analysis, the contingency (relation between R and
C) is manipulated by the experimenter
–
–
–
–
If R1, then C1 AND if other R then no C1 (R1->C and Rother -/-> C1)
The R-> C is a correlation - multiple instances of R (only) followed by C
The manipulated relation is the independent variable
Consequences must be under control of the experimenter to
demonstrate experimental control
• Operant behavior: Behavior (movements + effects) that can be
shown to be altered in a measurable way by consequences
• Operant behavior is said to be “selected by its consequences”3 –
The R-> C contingency results in a lineages of R of given properties
(“an operant”)
Schematic of Operant Contingency
Movements in
relation to the
environment (lever)
Effect on environment
(part of the behavioral
definition)
Operant
Recurring
lever presses
Contingent action
of external
environment
Consequence
Switch
Closures
Food
Pellet
All other behavior
Contingency
Increase in
relative frequency
of lever presses
in behavior stream
Operant Contingencies in A Behavior Stream
Organism O’s Behavior Stream (1 minute)
Situation S ----------------------------------------------------------------------------- Environment
R1 R2 R3 R4 R5 R2 R3 R6 R5 R4 R7 R1 R5 R6 R5 R8 R5 R7 R5 R5 R5 Behavior
C1
C1
C1
C1 C1 C1 Environment
• Contingency
– R5 always followed by C1
– Other R not followed by C1
• Contingency appears to be affecting frequency of R5
• Therefore R5 designated as “an operant” (a lineage of responses
undergoing selection by C1)
Functions of Consequences
• Events that are contingent on one or more
properties of operant responses
• Are classified according to how they function in
the contingencies
– Reinforcers – consequences in operant contingencies
that increase frequency of operant responses
– Punishers – consequences in operant contingencies
that decrease frequency of operant responses
– Neutral consequences– consequences in operant
contingencies that increase frequency of operant
responses
Three-Term Contingencies:
Stimulus Control
• Consequence can be made contingent on occurrence of R at a
particular time/place (stimulus conditons)
– If cafe sign reads “open”, opening the door results in access to coffee
– If cafe sign reads “closed”, opening the door does not result in access
to coffee
S1 * R -> C1; S2 * R -/-> C1
– This contingency will bring opening door under stimulus control of
“open” and “closed” signs IF coffee has current reinforcing function
• The “open” sign is called S+ (it signals availability of coffee) and the
“closed” sign S- (it “signals” unavailability of coffee)
• Result: S1 (“open”) and S2 (“closed”) acquire discriminative function
– When S1 (“open”) is present, opening the door is likely
– When S2 (“closed”) is present, opening the door is unlikely
Motivation4, 5
• The function of S+ may be temporarily altered
when coffee does not have current reinforcing
function
– Example: A person who recently had 3 cups of coffee
may not open the door to the café when the sign
“open” is present
• The frequency of behavior that has been
reinforced by a particular consequence depends
on two things:
– the current reinforcer value of the consequence
previously contingent on R in the presence of S+ and
– the presence of the “open” sign (S+)
Hierarchically Nested Operants
Operant Lineages
(Recurring operant
occurrences)
Elements of Each Occurrence
Press <Enter>
Place digit on key and depress
Open MS Word
Locate program icon on
desktop
Place cursor on icon
Press <Enter>
Copy email text into a
Word document
Open MS Word
Open email
Highlight test to be copied
Press <Ctrl C>
Press <Alt> and <tab>
Press <Ctrl V>
Organism O
Summary
• Operant behavior is behavior that operates on the environment to produce
reinforcing consequences (or to avoid punishing consequences)
• The contingency between occurrences of an operant and reinforcing
consequences account for (explain)
– Formal properties of the behavior
– Frequency of occurrence of the behavior
– Stimulus conditions under which the behavior is likely to occur
• Whether a particular consequence has reinforcing function and whether a
particular S+ makes behavior more likely at any given time may depend on
motivational operations
• Experimental analysis is accomplished by stripping experimental environment
of everything but the fundamental unit
• Operant behavior in the everyday world occurs at multiple scales (something
like function fractals)
References
1
2
3
4
5
Skinner, B. F. (1938). The behavior of organisms. Englewood Cliffs, NJ:
Prentice Hall.
Ferster, C.B. & Skinner, B. F. (1957). Schedules of reinforcement.
Englewood Cliffs, NJ: Prentice Hall.
Skinner, B. F. (1981). Selection by consequences. Science, 213, 501-504.
Michael, J. (1982). Distinguishing between discriminative and
motivational functions of stimuli. Journal of the Experimental Analysis of
Behavior, 37, 149-155
Laraway, S. Snycerski, S. Michael, J. & Poling, A. (2003). Motivating
operations and terms to describe them: Some further refinements..
Journal of Applied Behavior Analysis, 36, 407-414